The present invention relates to saws and more particularly to a dust and particle control attachment for rotary blade saws.
In any sawing or grinding operation employing a disk-shaped or circular rotary saw blade or rotatable grinding element, a considerable quantity of dust is produced as a rotatable element cuts or grinds through the material being sawed or ground. The volume and nature of the dust produced presents a particular problem in sawing stone, concrete or mortar.
At one time, the dust generated by sawing concrete with a rotary saw blade was controlled by directing a flow of water to the saw blade so as to both cool the saw blade and carry away the particulates of concrete or mortar dust generated as the saw cuts through the concrete or mortar. This necessitated a supply of water to the location at which the concrete or mortar was to be cut. In some locations, it is extremely difficult to provide a cooling water supply for a rotary saw blade used for cutting concrete or mortar. For example, mortar is often cut from between bricks on the side of a building for preparation of tuck pointing the bricks where the mortar has begun to crack and loosen. On tall buildings especially, it is extremely difficult to provide a cooling water supply to a concrete saw being used to saw out cracked mortar from between bricks.
In recent years, the cutting of mortar and concrete has been performed with power saws employing blades containing diamond cutting elements. Such implements are very advantageous since no cooling water supply is required where diamond tipped rotary blades are utilized. However, one major disadvantageous of the elimination of cooling water is the large amount of very fine dust generated during the sawing operation. The immediate environment of an individual operating the saw is filled with this very fine dust. The operator must therefore wear a mask to attempt to keep the dust out of his nose, mouth and lungs. Such masks are only partially effective, however. Furthermore, the clouds of dust generated reduce the operators' visibility, thereby slowing the pace at which the concrete can be cut.
As OSHA standards become tougher on free silica, contractors who cut masonry and other dust producing materials (sheetrock, other gypsum products, etc.) are forced to protect their workers and surrounding people from the dust hazard both on external and internal worksites.
In the past, it has been the focus of the people in the masonry grinding business or cutting business to focus on personal protective systems and gear for their employees. Dust was just one of the many hazards to deal with. The most effective system was a dust respirator developed for the mining industry. This worked well for many years. Then it was realized that even though the respirator protected the lungs from dust during cutting operations the residue dust that collected on clothing and the surrounding work environment was also a hazard.
Efforts were then made to contain the dust at the source. There are several manufacturers that provide a large selection of well engineered dust containment systems for both cutting and surface grinding. All of the products that have been used in the past fail to enable the cutting of the inside corner of abutting walls. It would be an advantage if the inside corners of abutting walls could be cut and ground in the same operation as the rest of the wall particularly on historical buildings with lots of moldings and ornamental detail.